
'Jeep*
UNIVERSAL SERIES SERVICE
MANUAL
N
REAR
AXLE
Contents
PAR. SUBJECT
PAR.
N-l POWR-LOK DIFFERENTIAL
N-20
Chatter
.N-26 Dissasembly and Reassembly. .N-23
Torque Test .N-22
21* Trouble Symptoms N-21
SUBJECT
GENERAL
REAR
AXLE SHAFT
AND
BEARING REMOVAL
Semi-Float-Tapered Axle Shaft
Semi-Float-Flanged Axle Shaft
Semi-Float-Flanged Axle Shaft
Bearing Installation. N-8
UNIT
BEARING ASSEMBLY
N-4 Servicing Unit Bearing. N-5
Lubricating
Unit Bearing............... N-6
Unit
Bearing Removal
.
N-7
REAR
AXLE ASSEMBLY
N-9 Cleaning and Inspection.
..............N-15
Differential Bearing Preload and Ring
Gear
Backlash Adjustment.
..........
.N-l9
Differential Case Disassembly N-l2
Differential Case Reassembly N-l7
Differential Side
Gear
Adjustment. . .... .N-18
Inspection and Servicing N-10 Pinion Bearing Cup Removal .N-l4
Pinion Installation and Adjustments. ... .N-l6 Pinion and Differential Bearing Removal N-13
Rear
Axle Assembly Removal N-ll
N-l. GENERAL
A
semifloating
rear axle assembly is standard on
all
Jeep Universal Series vehicles. Two
models
of
similar
design
rear
axles
are used. See Specifi
cations
Chart,
Par. N-38, for description and ratio.
The
axle
model
number is cast
into
the
housing
as
FIG.
N-l—AXLE MODEL IDENTIFICATION
illustrated in Fig. N-l. A metal tag under two ad
jacent differential
housing
cover cap screws is
stamped to
identify
the number of
teeth
in the
drive
gear
and pinion and
notes
the axle ratio. A
REAR
AXLE ASSEMBLY
INSTALLATION
N-33
TRAC-LOK
DIFFERENTIAL.
..........
.N-24
Lubrication
N-25 Trouble Symptoms N-26
Unit
Inoperative N-2 7 Disassembly N-28, N-29 Inspection .N-30
Reassembly .N-31
Trac-Lok
Unit Replacement .N-32
Backlash
N-35
TROUBLE
SHOOTING
DIFFERENTIAL
N-34
Rear
Wheel
Noise
.N-36
SERVICE
DIAGNOSIS
.N-37
REAR
AXLE SPECIFICATIONS.
. N-38
Powr-Lok
or
Trac-Lok
differential can be identi
fied by a separate metal tag attached to the
hous
ing cover, as shown in Fig. N-2. Information for wheel bearing adjustment is
given
in Section Q.
FIG.
N-2—RATIO,
POWR-LOK
AND
TRAC-LOK
DIFFERENTIAL IDENTIFICATION
1—Ratio Tag 2—Powr-Lok or
Trac-Lok
Tag
N-2.
REAR AXLE SHAFT REMOVAL
AND
INSTALLATION
(Semi-Float Tapered Shaft)
Procedure for removing the rear axle
shafts
is as
follows:
a.
Jack
up the wheel and
remove
the hub cap.
b. Remove wheel. 287

FIG.
N-3—SEMIFLOATING REAR
AXLE
—
TAPERED SHAFT
1— Differential Bearing Cup
2— Differential Bearing Cone and Rollers
3— Shims
4— Differential Case 5—
Ring
Gear and Pinion
6— Pinion Inner Bearing Cone and Rollers
7— Pinion Inner Bearing Cup
8— Pinion Shims
9— Axle
Housing
10— Pinion Outer Bearing Cup
11— Pinion Outer Bearing Cone and Rollers 12—
Oil
Slinger
13— Gasket
14— Pinion Oil Seal
15— Dust Shield
16— Yoke
17—
Flat
Washer
18— Pinion Nut 19— Wheel Bearing Shims
20— Bearing Cup
21— Bearing Cone and Rollers
22—
Oil
Seal 23—
Thrust
Washer
24— Differential Pinion Gears
25—
Thrust
Washer
26— Axle Shaft 27—
Thrust
Block
28— Gasket 29—
—Housing
Cover
30— —Screw and Lock Washer
31—
Filler
Plug 32— Differential Shaft
33—
Lock
Pin
34—
Ring
Gear Screw
c.
Remove the axle shaft cotter pin, castle nut,
and
flat washer.
d.
Back
off on brake adjustment eccentric.
FIG.
N-4—WHEEL
HUB
PULLER
e. Use Wheel Hub Puller C-319 to remove the
wheel hub as shown in Fig. N-4.
f. Remove the screws attaching the brake dust
protector, grease and bearing retainers, brake as
sembly, and shim to the housing.
g. Remove the hydraulic line from the brake as sembly.
h.
Remove the dust shield and oil seal.
i.
Using Tool C-637 and Adapter Tool SP-342,
remove the axle shaft bearing cone, roller, and cup
as shown in Fig. N-5.
j.
Should an axle shaft be broken, the inner end
can
usually be drawn out of the housing with a
wire
loop
after the outer oil seal is removed. How ever, if the broken end is
less
than 8" [20,3 cm.]
long it
will
usually be necessary to remove the
differential
assembly.
To
remove the bearing from an axle shaft, use
Combination
Bearing Puller W-104-B shown in
Fig.
N-6.
Installation
is the reverse of removal.
Note:
Place the hub and drum on the axle shaft
taper and then insert the axle shaft key in the
keyway.
Never install the key in the keyway before
placing
the hub and drum assembly on the axle
shaft
Further,
be sure that the axle shaft nut is torqued to a minimum of 150 lb-ft. [21 kg-m.j. 288

N
REAR
AXLE
FIG.
N-l3—NOTCHING
BEARING
RETAINING
RING
c.
Attach puller
tool
W-343 to axle shaft flanged
end using the wheel lug nuts. Position puller
bolts
against dimples of holding ring and alternately tighten until bearing is pressed from shaft, as shown
in
Fig. N-14. 14152
FIG.
N-14—REMOVING
AXLE
SHAFT
BEARING
1—
Bolt
2—
Flange
Adapter
3—
Dimple
in Holding
Ring
4 Holding
Ring
5—
Adapter
Plates N-8.
Rear
Axle
Shaft and Bearing Installation
(Semi-Float-Flanged
Shaft)
a.
Inspect the axle shaft oil seal
journal
for
scratches and polish with fine crocus cloth if
necessary.
b.
Install
retainer plate on the axle shaft
c.
Apply grease to the new oil seal cavity
between
the seal lips and carefully slide seal, on the axle shaft seal seat. The outer face of the seal must be
toward
the axle flange.
d.
Pack
the new bearing
full
of grease
prior
to
installation,
using the proper lubricant.
e.
Install
the unit bearing on the axle shaft making
certain
the cup rib ring is facing the axle flange.
f.
Install
the new bearing retainer ring on the axle shaft.
g. Using puller
tool
W-343, press the new axle shaft bearing and retainer ring on the axle shaft
simultaneously. Tighten puller
bolts
alternately
until
the bearing and retainer ring are properly
seated
against the shaft shoulder.
Refer
to Fig. N-15 and N-16. 14154
FIG.
N-15—INSTALLING
AXLE
SHAFT
BEARING
1—
Holding
Ring
2—
Adapter
3—
Flange
Adapter
4—
Bolt
Note:
Make certain the old bearing cup has
been
removed from the axle housing
before
the axle
shaft and new unit bearing is installed
into
the
axle housing.
h.
Install
axle shaft through the backing plate
using care not to damage the axle housing
tube
inner
oil seal.
i.
Apply a thin coating of lubricant to the
outside
diameter of the bearing cup
prior
to installing in
the bearing bore.
j.
Tap end of flanged shaft lightly with a rawhide
mallet to position the axle shaft bearing in the
housing bearing bore.
k.
Attach the axle shaft retainer and brake back
ing plate to the axle
tube
flange. Secure with nuts
and
lockwashers. Torque 25 to 35 lb. ft
[3,4-4,8
kg-m.].
I.
Install
a new cup plug
into
the axle shaft
flange
hole.
m.
Install
the brake
drum,
and
rear
wheel as
sembly. 292

N
REAR
AXLE
with
a micrometer and add
together
to get total
shim
pack thickness from original buildup.
Note
the (-j-) or (—) etching on both the old pinion and the new one, and adjust the thickness of new shim
pack
to compensate for the difference
between
these
two figures. Refer to chart for example. If the old pinion reads (+2) and the new pinion is (—2),
add
.004" shims to the original pack dimension. Now build a new shim pack to this resulting di
mension.
m.
When the correct adjustment is reached, remove
the pinion adjusting fixture and
sleeve
SP-1997.
Install
outer bearing.
n.
Install
only the oil slinger, the yoke, the flat
washer,
and the pinion nut Holding the yoke with
Flange
Holder C-3281, torque the nut 200 to 220 lb-ft. [27,65 a
30,42
kg-m.].
o. Using Inch-Pound Torque Wrench W-297 on
the nut check the rotating torque. The rotating torque should be 10 to 25 lb-in. [0,115 a
0,288
kg-m.].
p. Add or remove shims
between
the pinion outer
bearing and the pinion shaft to obtain correct
torque reading.
N-l7.
Differential Case Reassembly
Procedure
for assembling the differential case on semifloating
rear
axles is as follows:
a.
Reassemble the differential pinions, side gears,
thrust
washers, and shaft in relative position shown
in
Fig. N-3 and N-7. Make sure the spacers are
installed.
b.
Install
differential shaft lock pin.
Note:
Disregard starting torque.
Old
Pinion
NEW
PINION MARKING
-4 -3
-2 _1
0
+4
+0.008
+0.007
+0.006 +0.005 +0.004
+3
+0.007 +0.006
+0.005 +0.004
+0.003
+2
+0.006
+0.005
+0.004 +0.003 +0.002
+1
+0.005 +0.004
+0.003 +0.002 +0.001
0
+0.004
+0.003 +0.002
+0.001
0
_1
+0.003 +0.002 +0.001
0
-0.001
-2
+0.002 +0.001
0
-0.001 -0.002
-3
+0.001
0
-0.001 -0.002
-0.003
-4
0
-0.001 -0.002
-0.003 -0.004
Old
Pinion
Marking
NEW
PINION MARKING
Old
Pinion
Marking
+1 +2
+3
+4
+4
+0.003 +0.002 +0.001
0
+3
+0.002
+0.001
0
-0.001
+2
+0.001
0
-0.001 -0.002
+1 0
-0.001
-0.002 -0.003
0
-0.001 -0.002
-0.003 -0.004
-1
-0.002 -0.003
-0.004
-0 005
-2
-0.003 -0.004 -0.005 -0.006
-3
-0.004 -0.005
-0.006 -0.007
_4
-0.005 -0.006
-0.007 -0.008
FIG.
N-30—DIFFERENTIAL
SHIM PACK LOCATIONS
298

'Jeep9
UNIVERSAL
SERIES SERVICE
MANUAL
N
c.
Check
side gear clearance as described in Par.
N-18.
d.
Examine contacting surfaces of ring gear and
differential case for
burrs
or foreign matter.
e.
Assemble ring gear on differential case with assembly
hole
on each lined up.
f.
Tap ring gear
into
place with mallet.
g.
Install
ring gear screws. Torque 35 to 55 lb-ft. [4,84 a 7,60 kg-m.].
N-18.
Adjustment
of
Differential
Side
Gears
Clearance
between
the differential side gears and differential case should be .000" to .006"
[0,000
a
0,192 mm.] Procedure for checking clearance is as
follows:
a.
With
the differential positioned as shown in
Fig.
N-31, tap the differential lightly on a flat
sur
face so the differential gears
settle
into
proper
position.
b. Measure the clearance
between
side gears and
the case with leaf feeler
gauge
as illustrated. c. If the clearance
exceds
.006" add shims
between
the side gears and the case. To bring the clearance
within specified tolerance, shims in
these
thick
nesses
are available.
.004"
[0,102
mm.], .006"
[0,152
mm.], .008"
[0,203
mm.].
If shims are required, at least one shim
should be placed on each side and the shim packs kept as even as possible. After adding shims, repeat
the clearance check.
10009
FIG.
N-31—CHECKING SIDE GEAR CLEARANCE N-l9.
Adjustment of
Differential
Bearing Preload
and
Ring
Gear
Backlash
Refer
to Fig. N-30.
The
adjustment of the differential bearings is main
tained by the use of shims placed
betwen
the dif
ferential case and the differential bearing. Proce
dure for adjusting bearing preload is as follows:
a.
Install
the differential case and bearings in the
axle housing without shims and with the bearing
cups snug.
b. Holding the ring gear in contact with the pinipn
and
using a screwdriver blade to
move
the differen
tial
bearing cups toward the center, insert feeler
gauge
on each side
between
differential bearing cup and the axle housing.
There
should be only
.001" to .002"
[0,025
a 0,051 mm.] backlash
remaining with the feeler
gauge
inserted.
c.
After the shim pack requirement for each bear
ing has
been
established remove the differential
assembly. Make up shim packs and
keep
them separated.
d.
Add an additional .015"
[0,381
mm.] thickness:
of shims to the pack on the
tooth
side of the ring gear.
e.
Place the differential bearing shim packs on the
differential case under each bearing.
Install
bear
ings
with
Driver
C-3716 for Model
27AF
axles
and
Driver
W-188 for Model 44 axles. See Fig. N-32.
Note:
When overhauling the Model
27AF
front
axle differential, check the axle inner oil seals. Should new seals be required, install them using
Tool
W-128 as shown in Fig. N-33. When installing
the axle differential in the axle housing, use
Spreader
Tool W-129.
f. Attach the
Carrier
Spreader W-129, (see
note
Par.
N-12) install a
dial
indicator, (Fig. N-19) and spread the
carrier
a maximum of .020"
[0,508
mm.].
FIG.
N-32—DIFFERENTIAL BEARING DRIVER
299

N
REAR AXLE
11874
FIG.
N-33—INSTALLING INNER OIL SEALS — MODEL 27 FRONT
AXLE
DIFFERENTIAL g. Remove the indicator.
h.
Lubricate bearings and place the differential in
the
carrier.
i.
Tap the unit carefully
into
place with
soft
mallet, making sure the ring gear
teeth
mesh with the
pinion
teeth.
j.
Install bearing caps, matching their markings
with
those
on the
carrier.
k. Apply sealing compound to the screw threads.
Torque
the screws 70 to 90 lb-ft. [9,68 a 12,44
kg-m.].
I.
Install dial indicator to check ring gear back
lash
(Fig. N-34). Check backlash at two points.
Backlash
must be held
between
.005" to .010"
[0,127
a
0,254
mm.]. If backlash
does
not fall with
in
specifications, shims should be interchanged be
tween
the two differential bearing shim packs until
correct backlash is obtained.
Note:
Changing the position of a .005"
[0,127
mm.]
shim from one side to the other
will
change the
amount of backlash approximately .003"
[0,076
mm.].
m. Check ring gear for runout. A reading in
excess
of .006"
[0,152
mm.] indicates a sprung differential
case, dirt
between
the case and the gear, or
loose
ring
gear screws.
n.
In order to assist in determining whether the
gears are properly adjusted, paint the bevel gear
teeth
with red lead or prussion blue and turn the
bevel gear so the pinion
will
make an impression on the
teeth.
The correct procedure to
follow
in the
event
of an unsatisfactory
tooth
contact is shown
in Fig.
N-35.
o. After the differential has
been
assembled and
adjusted, the pinion shaft oil seal should be in
stalled.
THE
HEEL
OF
GEAR TOOTH
IS THE
LARGE
END,
AND THE TOE IS THE
SHALL
END.
WORKING DEPTH
TOO
MUCH BACK LASH
MOVE GEAR TOWARD PINION
TOO
LITTLE BACK LASH
MOVE GEAR AWAY FROM PINION
\:
US33
FIG.
N-34—CHECKING RING GEAR BACKLASH
MOVE
PINION
OUT
AWAY FROM RING GEAR MOVE PINION
IN
TOWARD RING GEAR
CORRECT SETTING COMPROMISE SETTING
10547
FIG.
N-35—GEAR
TOOTH CONTACT 300

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL
N
13189
FIG.
N-36—PINION
SHAFT OIL
SEAL
INSTALLER
1—Tool
W-147
p.
Remove
the
sleeve
previously installed in
place
of
the yoke. Install the oil
seal
with
Tool
W-147 shown in Fig. N-36.
q. Install the yoke
with
Flange
Installer W-162,
as shown in Fig. N-3 7.
r.
Install pinion nut and cotter pin.
s. Install axle
shafts
and housing cover.
N-20.
POWR-LOK
DIFFERENTIAL
As
optional equipment, Powr-Lok was previously available on all
Jeep
Universal
models
equipped
with
semi-float
tapered
axle
shafts.
The Powr-Lok
differential
may be identified by a tag located on
the opposite
side
of the differential housing
from
the ratio tag (Fig. N-2) and
stamped
with
either a "T" or
with
the words, "USE
LIMITED
SLIP
FIG.
N-37—YOKE INSTALLING TOOL
DIFF.
LUBE
ONLY."
This differential is available
for
rear
axles
only.
Whenever a
replacement
or conversion Powr-Lok
differential
is to be installed in an axle which has
been
previously in
service
and acquired mileage, be
sure
to record the amount of backlash
between
the ring
gear
and pinion at the time of
disassembly.
When the axle is again
assembled
the ring
gear
and pinion must be set to this
same
amount of
back
lash.
Axle
ratios and
speedometer
gear
application is very important. In
like
model
axles,
the ratio may
be
changed
by simply changing to the desired ring
gear
and pinion;
except
in the
case
of the
3.73:1
or higher ratios. When changing
from
a
3.73:1
or higher to 3.54 or lower ratio, or vice
versa,
the
differential
case
must
also
be
changed
on a
stand
ard differential
assembly,
and the differential as sembly,
less
ring
gear
and pinion, when a Powr-Lok
differential
assembly
is involved. When changing
from
any ratio to
another,
it
will
also
be
necessary
to
change
speedometer
gears.
Speedometer
gears
for
Powr-Lok and
standard
differentials of the
same
ratio, are
interchangeable.
A complete
rear
axle
assembly
replacement
is
necessary,
if a con
version
from
one type of differential
assembly
to
another
is desired.
Note: Powr-Lok differentials use a special
lubri
cant.
Refer to the Lubrication Chart.
N-21.
Trouble Symptoms and
Possible
Causes
If
noises
such
as
chatter
are
detected,
when turning
a corner, the probable
reason
for this is that incor
rect
gear
lubricant has
been
installed in the axle.
Axles
equipped
with
a
limited
slip differential require special lubricant. Refer to Lubrication
Sec
tion,
Par. B-52.
Note: It may be
necessary
to use an additive to
attempt to eliminate
chatter.
If this is not
success
ful
then
disassembly
and inspection of the differen
tial
becomes
necessary.
Warning:
Extreme
care
must be exercised on a
Powr-Lok
equipped vehicle to be
sure
the transmis
sion is in the neutral position
whenever
the
engine
is
started
with
one wheel jacked up. Otherwise the
vehicle may lurch unexpectedly and
fall
off the
jack.
N-22. Torque Test
Procedure
for testing torque Powr-Lok differentials
on
Jeep
Universal
Series
vehicles is as follows:
FIG.
N-38—POWR-LOK DIFFERENTIAL
1—
Differential
Case Flange
Half
2—
Disc
and Plate Set
3—
Side
Gear
Ring
4— Side
Gear
and Pinion Mate
Gear
Set
5—
Pinion
Mate
Cross
Shaft 6—
Differential
Case Button
Half
7—
Axle
Shaft Spacer
8—
Axle
Shaft Spacer
Roll
Pin 11564
301

N
REAR
AXLE a.
Place the transmission in neutral.
b.
Raise one wheel off the floor and place a block
in
front and at the
rear
of the
opposite
wheel.
c.
Apply a torque wrench to the axle shaft nut of
the elevated wheel.
d.
Turn
wheel with torque wrench. Disregard
breakaway
torque and observe torque required to
continuously
turn
wheel smoothly. Torque should
read
40 lb-ft [5,53 kg-m.] or more.
N-23. Powr-Lok
Differential Disassembly
/
and Reassembly
Refer
to
Figs.
N-38 and N-39.
The
procedure for overhauling disc type
Powr-Lok
differentials is as follows:
a.
Remove axle shafts following procedure de
scribed
in Par. N-2.
b.
Remove housing cover and gasket.
c.
Remove the
Powr-Lok
differential from the axle.
Do not remove the ring gear or bearing
cone
and
rollers
unless replacement is to be made.
Mark
the hearing cups so they may later be reassembled
with
the same bearing cones.
Mark
the differential
case halves for correct alignment at reassembly.
Each
pinion mate cross shaft should also be marked
so that each pin cam surface
will
match with the
same
V-ramp
in the case when reassembled.
d.
Separate the case halves. e. Remove the disc and plate
sets.
The illustration
(Fig.
N-39) shows the arrangement of plates and
discs.
When reassembling unit, discs and plates must be reinstalled in this arrangement. Be sure
to keep in mind which way the set
will
face toward the case.
^®(j)(j)CD©
® /'Ml
I
11
11 v
FIG.
N-39—PLATE
ASSEMBLY
ORPER
A—Model
44
B—Model
27 1—
Case
5—Disc
2—
Belleville
Plate
6—Thin
Plate
3—
Belleville
Disc
7—Sidegear
Ring
4—Plate
8—Side
Gear
f. Remove the pinion mate cross shafts, bevel
pinion mate gears, bevel side gears, and side gear
rings.
g.
Clean
all parts thoroughly in kerosene and dry
with
compressed air.
h.
Inspect all parts. Replace any items which ap
pear
to be worn or damaged.
i.
Inspect the plate surfaces of the case halves, the
side gear rings, and the clutch friction plates and
discs for excessive wear or scoring.
j.
Inspect the pinion mate shaft and ramp
sur
faces on the case for excessive wear and pitting,
k.
Inspect the pinion gear races that bear on the
side gear rings.
I.
Inspect the corresponding surfaces on the side
gear rings.
m.
Inspect the clutch plates and discs for cracks
and
distortion. In the
event
one or more of the
clutch
plates or discs
needs
replacing, replace the
entire stack of plates and discs on each side of
the pinions. These stacks are supplied in
sets.
The
differential case halves are not serviced. Should replacement be required, it is necesary to replace
the complete differential.
n.
Assemble the clutch friction plates, clutch
fric
tion discs, and dished plates on the splined hub of each bevel side gear. Make sure the plates and
discs are installed in the proper relationship as shown in Fig. N-39. The dished plates in the plate
and
disc set are always assembled with the convex
side toward the case. As each part is reassembled
in
its proper position, it is necessary that it be lightly coated with
Powr-Lok
lubricant,
o.
Place each differential case
half
on its side and
install
the side gear rings with the plates and discs
assembled. The side gear ring
will
rotate with a slight drag when properly located in the case,
p.
With
the ring gear flange
half
of the differential
case in an upright position, assemble the bevel side gears, pinion mate cross shafts, and bevel pinion
mate gears.
Install
the remaining case
half
on the
ring
gear flange half. Make sure that all markings
coincide.
q.
Install
the differential case
bolts
and
turn
them
in
a few threads.
r.
Using axle shafts from the vehicle, align the
splines of the side gear, and the side gear
ring,
s.
With
these
axle shafts in position, tighten the
differential
case
bolts
evenly. Torque 35 to 45 lb-ft. [4,84 a 6,22 kg-m.].
t. Remove the axle shafts.
u.
Check
for proper assembly.
Each
pinion mate
cross shaft should be tight on its
ramp.
If there is
clearance
between
the cross shaft and the
ramp,
the clearance should be no more than .005" [0,127 mm.].
This
clearance should be equal on all four cross
shaft ends.
v. Reinstall the unit in the axle.
w.
Install
axle shafts as described in Par. N-2.
Other
service operations such as ring gear and
pinion replacement, or pinion and bearing adjust ments, are performed in the same manner as de- 302